Orientador: Antonio Ludovico Beraldo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-19T15:40:14Z (GMT). No. of bitstreams: 1 Matsuoka_JessicaHarue_M.pdf: 8291603 bytes, checksum: 8efcc65849d53bfd555a92bc8450b072 (MD5) Previous issue date: 2011 / Resumo: O bambu apresenta inúmeras características que o qualificam como um material versátil e que há milhares de anos vem servindo como matéria-prima para diversos fins, fazendo parte da história e da cultura de muitos povos. Muitas pesquisas vêm sendo realizadas acerca da utilização do bambu em setores diversos como da construção civil, movelaria e produção de celulose, visando à promoção de um desenvolvimento mais sustentável. Por se tratar de um recurso renovável, o uso do bambu tem o potencial de minimizar os impactos negativos ao meio ambiente e reduzir os custos da produção, além de apresentar excelentes propriedades físico-mecânicas. Dentre as espécies cultivadas no Brasil, o bambu gigante (Dendrocalamus giganteus Munro), de origem asiática, destaca-se na utilização para construção civil, em aplicações estruturais, arquitetônicas e em movelaria. No entanto, a baixa resistência natural da maioria das espécies ao ataque de organismos xilófagos é ainda uma das principais limitações ao seu uso, implicando em graves prejuízos econômicos. Por este motivo, muitos tratamentos preservativos vêm sendo desenvolvidos, com o intuito de prolongar a vida útil do bambu e aumentar sua resistência contra os agentes deterioradores. Este trabalho teve como objetivo identificar os principais gêneros de fungos deterioradores de bambu e desenvolver um método de tratamento preservativo que fosse eficiente no controle da deterioração do bambu por fungos e que minimizasse as características negativas inerentes aos tratamentos químicos ora existentes e ao impacto ambiental por eles causado. Desta forma, investigou-se a possibilidade de utilização do ácido pirolenhoso, produto obtido a partir do processo de carbonização de matéria vegetal. Foram testadas diversas concentrações e tempos de tratamento e realizados ensaios de apodrecimento acelerado em laboratório e ensaios não destrutivos e destrutivos para verificação da eficiência no controle à degradação por fungos. Os gêneros de fungos foram previamente isolados e identificados em ensaios de simulação de exposição em campo. Pela análise estatística dos resultados não houve diferença significativa entre os corpos-de-prova tratados e não tratados. Devido ao limitado período de 16 semanas de duração do ensaio, não foi possível avaliar a ação protetora do ácido pirolenhoso, nas concentrações e tempos de imersão utilizados, quanto à sua eficiência no tratamento preservativo das taliscas de bambu gigante contra deterioração por fungos / Abstract: Bamboo can be considered as a versatile material because of its many features and so it has been used for thousands of years serving as raw material to numerous uses, being part of many people's history and culture. Many researches have been conducted about bamboo uses in several areas, such as construction, furniture making and cellulose production, with the objective to promote a sustainable development, in which bamboo can substitute the conventional materials, especially wood. As bamboo is a renewable resource, it can reduce the negative impact to environment, minimize costs and also presents excellent physical and mechanical properties. There are many cultivated species in Brazil, such as the giant bamboo (Dendrocalamus giganteus Munro), an Asian specie that is largely used on construction, in structural and architectural applications and to furniture production. However, most species of bamboo has low natural resistance to the wood decay organisms, which still constitutes one of the major limitations to its use and can cause several economic damages. For this reason, many preservative treatments have been developing, aiming to increase bamboo life cycle and its resistance against decay agents. This work had as objective to identify the main genera of wood decaying fungi and develop an efficient preservative treatment method that controls fungal bamboo decay and minimize the negative features intrinsic to existing chemical treatment and the environmental impact caused by them as well. It was investigated the possibility of using a pyroligneous acid, which is obtained from the vegetal coal production process. Several concentrations and time of treatment were tested and specimens were submitted to an accelerated decay test in laboratory and non-destructive and destructive tests to verify the product efficiency against fungi decay. Fungi genera were previously isolated and identified through a test that simulated field exposure. The statistical analysis from the results indicated no significant difference between treated and non-treated specimens, however, due to the short period of 16 week of the essay, it wasn't possible to evaluate the protective activity of pyroligneous acid, for the concentrations and times of treatment applied to the strips, about its efficiency on preservative treatment against bamboo fungi decay / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola

Orientadores: Lucia Regina Durrant, Alexandre Nunes Ponezi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-20T15:30:45Z (GMT). No. of bitstreams: 1 Santos_IvanJoseSantana_M.pdf: 1134875 bytes, checksum: 88af103bdbd26ade9ec5e063cbd582c5 (MD5) Previous issue date: 2012 / Resumo: 17a-etinilestradiol (EE2), carbamazepina (CBZ) e ibuprofeno (IBU) são substâncias farmacêuticas muito utilizadas em todo o mundo e vêm sendo frequentemente detectadas em estações de tratamento de efluentes e em águas naturais em vários países, inclusive no Brasil. A grande preocupação da presença destes fármacos em quantidades residuais na água potável e nos ambientes aquáticos são os potenciais efeitos adversos para a saúde humana e animal. O objetivo principal deste trabalho foi avaliar o potencial de fungos ligninolíticos e bactérias para degradar esses três compostos, individualmente. Linhagens de bactérias e fungos ligninolíticos foram crescidas em meio mineral com os fármacos, na presença ou ausência de glicose. Primeiramente, foi realizada uma seleção com o objetivo de escolher linhagens bacterianas e fúngicas com maior capacidade de degradação dessas drogas, avaliando a necessidade da presença de glicose para que a degradação ocorresse. As linhagens que apresentaram maior capacidade de degradar tais compostos foram selecionadas e, em seguida, foram realizados ensaios com o intuito de se otimizar o período de incubação, visando-se uma maior porcentagem de degradação no menor período de incubação possível. Posteriormente, foram realizadas análises de atividade das enzimas lacase, lignina peroxidase (LiP) e manganês peroxidase (MnP) produzidas pelos fungos selecionados e foi avaliada a participação dessas na degradação dos fármacos. A atuação das enzimas do Citocromo P450 na degradação dos fármacos foi avaliada por meio da adição de piperonil butóxido (PB), o qual inibe esse complexo enzimático. A toxicidade dos fármacos e seus metabólitos para a bactéria Vibrio fischeri também foram avaliadas. A quantificação dos fármacos em todas as amostras foi realizada por meio de cromatografia líquida de alta eficiência. EE2 foi totalmente degradado por todos os fungos avaliados, sem a necessidade de glicose no meio de cultivo; no entanto, nenhuma das bactérias estudadas foi capaz de degradá-lo significativamente. Pleurotus ostreatus (Jacq.) P. Kumm linhagem P1 foi selecionado para os ensaios subsequentes. Após 6 dias, foi encontrada atividade de MnP igual a 5122,11 U.L-1. A lacase teve como atividade 307,69 U.L-1, valor encontrado após 4 dias de incubação. Não foi detectada atividade da enzima LiP em nenhum dos tempos analisados. Apesar da detecção de atividade dessas enzimas, elas não foram capazes de degradar o EE2 na ausência do micélio fúngico. Nos ensaios de toxicidade foi encontrada uma CE50 igual a 76% para o EE2 e os metabólitos não apresentaram toxicidade. Trametes sp. linhagem BNI foi a selecionado para degradar CBZ, sendo a glicose necessária para o processo de biodegradação. Após 28 dias de incubação, houve 42% de degradação de CBZ. A atividade máxima de lacase foi de 1740,17 U.L-1, sendo encontrada após 21 dias de incubação. LiP teve como atividade máxima 663,08 U.L-1, valor encontrado após 14 dias de incubação. Não foi detectada atividade da enzima MnP em nenhum dos tempos analisados. Não houve a degradação de CBZ utilizando apenas o caldo enzimático. A presença de PB inibiu totalmente a degradação de CBZ. CBZ e seus metabólitos não apresentaram toxicidade. Nenhuma das bactérias foi capaz de degradar CBZ. IBU foi totalmente degradado por todos os fungos avaliados sem a necessidade de glicose no meio de cultivo, sendo Trametes sp. linhagem BNI selecionado para os ensaios posteriores. Após 2 dias de incubação, BNI foi capaz de degradar totalmente IBU. Lacase foi a única enzima que teve atividade detectada nesse ensaio, sendo a atividade máxima detectada igual a 478,18 U.L-1, no sexto dia de incubação. Não foi detectada degradação de IBU utilizando apenas o caldo enzimático e a presença de PB no meio não inibiu a degradação deste fármaco. Nos ensaios de toxicidade foi encontrada uma CE50 igual a 86% para o IBU e os metabólitos não apresentaram toxicidade. Staphylococcus arlettae e Bacillus megaterium foram capazes de degradar significativamente IBU na presença de glicose. B. megaterium foi selecionado para os ensaios subsequentes. Após 3 dias, essa linhagem foi capaz de degradar todo IBU disponível no meio. Nos ensaios de toxicidade para os metabólitos do processo de biodegradação por B. megaterium, o IBU apresentou uma CE50 inicial igual a 47% e os metabólitos não apresentaram toxicidade. Esses resultados comprovam que fungos ligninolíticos e bactérias são capazes de degradar fármacos encontrados em matrizes ambientais, sendo plausível a utilização destes micro-organismos, ou suas enzimas, em sistemas de tratamento de água e esgoto / Abstract: 17a-ethinylestradiol (EE2), carbamazepine (CBZ) and ibuprofen (IBU) are pharmaceutical drugs used worldwide and have been frequently detected in wastewater treatment plants and in natural waters in several countries, including Brazil. The major concern about the occurrence of these drugs in trace amounts in drinking water and aquatic environments are the potential adverse effects on human and animal health. The main objective of this study was to assess the potential of ligninolytic fungi and bacteria to degrade these 3 compounds individually. Bacteria and ligninolytic fungi strains were grown on mineral medium with these drugs and with or without glucose. A selection was carried out to choose bacterial and fungal strains with capacity to degrade these drugs and if an addition of a carbon source (glucose) was needed for degradation. Strains with greater capacity to degrade these compounds were selected and assays were performed in order to optimize the incubation time to obtain the highest degradation rate in the shortest incubation time. Subsequently, the enzymatic activities of laccase, lignin peroxidase (LiP) and manganese peroxidase (MnP) produced by the selected fungi was assessed. Also, the action of these enzymes in the degradation of the drugs was evaluated. The involvement of cytochrome P450 enzymes in degradation of the pharmaceutical drugs was evaluated by the addition of piperonyl butoxide (PB), which inhibits this enzyme complex. The toxicity of the drugs and metabolites to Vibrio fischeri were also evaluated. The quantification of the drugs was performed by high performance liquid chromatography. EE2 was completely degraded by all fungi without glucose in the medium, however none of the studied bacteria was capable to degrade it significantly. Pleurotus ostreatus (Jacq.) P. Kumm strain P1 was selected for subsequent tests. The maximum enzyme activity produced by P1 was 5122.11 UL-1 for MnP after 6 days and 307.69 UL-1 for lacase after 4 days, while LiP activity was not detected. Although the detection of the enzymes activity, they were not able to degrade EE2 without the fungal mycelia. Toxicity studies showed the half maximal effective concentration (EC50) value equal to 76% to EE2 prior to fungal treatment, after this no toxicity was observed. Trametes sp. strain BNI was selected to degrade CBZ, and glucose was shown to be necessary for the biodegradation process. After 28 days of incubation, 42% of CBZ was degraded. The maximum laccase activity was 1740.17 UL-1, after 21 days of incubation. LiP maximum activity was 663.08 UL-1, found after 14 days of incubation, while MnP activity was not detected. There was no CBZ degradation using only the enzymatic supernatant. The addition of PB completely inhibited the degradation of CBZ. CBZ and its metabolites did not show toxicity. IBU was completely degraded by all fungi without glucose in the medium, and Trametes sp. strain BNI was selected for further analyses. 17a-ethinylestradiol (EE2), carbamazepine (CBZ) and ibuprofen (IBU) are pharmaceutical drugs used worldwide and have been frequently detected in wastewater treatment plants and in natural waters in several countries, including Brazil. The major concern about the occurrence of these drugs in trace amounts in drinking water and aquatic environments are the potential adverse effects on human and animal health. The main objective of this study was to assess the potential of ligninolytic fungi and bacteria to degrade these 3 compounds individually. Bacteria and ligninolytic fungi strains were grown on mineral medium with these drugs and with or without glucose. A selection was carried out to choose bacterial and fungal strains with capacity to degrade these drugs and if an addition of a carbon source (glucose) was needed for degradation. Strains with greater capacity to degrade these compounds were selected and assays were performed in order to optimize the incubation time to obtain the highest degradation rate in the shortest incubation time. Subsequently, the enzymatic activities of laccase, lignin peroxidase (LiP) and manganese peroxidase (MnP) produced by the selected fungi was assessed. Also, the action of these enzymes in the degradation of the drugs was evaluated. The involvement of cytochrome P450 enzymes in degradation of the pharmaceutical drugs was evaluated by the addition of piperonyl butoxide (PB), which inhibits this enzyme complex. The toxicity of the drugs and metabolites to Vibrio fischeri were also evaluated. The quantification of the drugs was performed by high performance liquid chromatography. EE2 was completely degraded by all fungi without glucose in the medium, however none of the studied bacteria was capable to degrade it significantly. Pleurotus ostreatus (Jacq.) P. Kumm strain P1 was selected for subsequent tests. The maximum enzyme activity produced by P1 was 5122.11 UL-1 for MnP after 6 days and 307.69 UL-1 for lacase after 4 days, while LiP activity was not detected. Although the detection of the enzymes activity, they were not able to degrade EE2 without the fungal mycelia. Toxicity studies showed the half maximal effective concentration (EC50) value equal to 76% to EE2 prior to fungal treatment, after this no toxicity was observed. Trametes sp. strain BNI was selected to degrade CBZ, and glucose was shown to be necessary for the biodegradation process. After 28 days of incubation, 42% of CBZ was degraded. The maximum laccase activity was 1740.17 UL-1, after 21 days of incubation. LiP maximum activity was 663.08 UL-1, found after 14 days of incubation, while MnP activity was not detected. There was no CBZ degradation using only the enzymatic supernatant. The addition of PB completely inhibited the degradation of CBZ. CBZ and its metabolites did not show toxicity. IBU was completely degraded by all fungi without glucose in the medium, and Trametes sp. strain BNI was selected for further analyses / Mestrado / Ciência de Alimentos / Mestre em Ciência de Alimentos

Orientador: Lucia Helena Innocentini Mei / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-03T19:31:20Z (GMT). No. of bitstreams: 1 Talamoni_JoaoRoberto_M.pdf: 3179199 bytes, checksum: 8fe9d391161838e5f0a3bd3360ef2652 (MD5) Previous issue date: 2003 / Resumo: Anualmente, são produzidas cerca de 110 milhões de toneladas de plásticos no mundo, e pelo menos a metade desta quantidade é rapidamente descartada sem qualquer cuidado, permanecendo em aterros e na natureza por décadas, gerando um custo ambiental muito alto. Na tentativa de minimizar este problema, muitos cientistas passaram a investir em pesquisas na tentativa de descobrir materiais que substituam estes plásticos e que ao mesmo tempo sejam ambientalmente amigáveis, ou seja, quando em contato com o solo e em ambientes propícios, estes novos materiais se degradem rapidamente. Muitas linhas de pesquisas trabalham com polímeros de origem natural, outras com síntese microbiológica, porém, uma das linhas de pesquisas mais forte neste sentido é a síntese e modificação de poliésteres alifáticos, que sabidamente possuem boas propriedades de biodegradação. Assim, o objetivo deste trabalho foi sintetizar, caracterizar e modificar um poliéster alifático com boas propriedades de biodegradação. Partiu-se de monômeros conhecidos, como o ácido adípico e o monoetileno glicol, e ainda usou-se outros materiais para tentar melhorar as propriedades dos polímeros sintetizados, como o glicerol e o diisocianato de hexametileno, este último usado para se obter poliésteres-uretanos de massa molar maior, menor cristalinidade e de mais fácil biodegradação. Todas as amostras obtidas foram caracterizadas via medições de suas massas molares por Cromatografia por Permeação em Gel e Viscosidade Intrínseca, e ainda mediuse a efetividade das reações através da Espectroscopia por Infravermelho. Também determinou-se as temperaturas de cristalização e de fusão através da Calorimetria Diferencial Exploratória e a perda de massa através de Análise Termogravimétrica. Ainda, acompanhou-se o processo de biodegradação através de fotos e microscopia ótica. Os resultados obtidos neste trabalho mostraram que a síntese de poliésteres alifáticos requer muitos cuidados para que se obtenha materiais com boas propriedades de aplicação, e que as modificações via isocianato, obtendo-se poliésteres-uretanos, é um caminho bastante interessante para a melhoria destas propriedades, e ainda, pode-se concluir que a síntese destes materiais é bastante promissora para se obter materiais / Abstract: Annually, about 110 millions of tons of plastics are produced around the world, and at least haIf of this amount is wasted speciaIly in landfills, remaining there for decades, causing high1y environmental costs. In order to solve this problem, many scientists are performing researches trying to create new materiaIs with adequate properties to replace these plastics and at the same time, materiaIs that are environmentally mends, and can be degraded when in contact with soil and under adequate conditions. Many researchers are working with natural polymers, others with polymers synthesized through microbiologicaI conditions, and others are working with the synthesis and modification of aIiphatic polyesters, which are known since decades that they are good biodegradable materiaIs. The objective of this work is the synthesis, characterization and modification of aIiphatic polyesters with good biodegradable properties. It was used known monomers for the synthesis, like adipic acid and ethylene glycol, and others materiaIs to improve properties, like glycerol and hexamethylene diisocyanate, this last one was used to obtain a polyester-urethane, with high molecular weight and lower degree of crystallization, improving its ability to degrade. All samples synthesized were characterized by Gel Permeation Chromatography and Intrinsic Viscosity to measure their molecular weight, and the effectiveness of the reactions were followed by Fourier-Transform Infrared Spectroscopy. Melting and Glass Transition temperatures and Crystallization behavior were measured through Differential Scanning Calorimetry. Using Thermogravimetry measurements, the loss of mass of all samples with temperature was measured. The biodegradation process was followed by periodical photos and with Optical Microscopy. The final results showed that the synthesis of aliphatic polyesters need to be carefully carried out to achieve materials with good properties, and the extension of these aliphatic polyesters with isocyanates is a viable way to increase properties of these materials, but it is possible to conc1ude that the synthesis of such materials is a very promising field to have biodegradable materials / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química

[pt] A mobilidade dos hidrocarbonetos de petróleo e os processos de remediação aos quais estão sendo submetidos são de fundamental importância para o gerenciamento de áreas contaminadas. A biorremediação é uma tecnologia multidisciplinar, que envolve ciências como a microbiologia, a engenharia, a geologia e a química, baseada na habilidade dos microrganismos de utilizar o contaminante como fonte exclusiva de energia para o funcionamento de seu metabolismo. O estudo de solos residuais tropicais é de valiosa contribuição para a comunidade científica brasileira por serem encontrados poucos trabalhos na literatura a respeito do comportamento de contaminantes orgânicos nestes solos. O objetivo desta dissertação de mestrado foi estudar a mobilidade de um óleo mineral em um solo arenoso inerte e em um solo residual indeformado. Neste último, em se tratando de um solo microbiologicamente ativo, foram também analisadas a biodegradação do contaminante e a influência da temperatura na atividade degradadora e na descida do óleo. Os ensaios com o solo arenoso inerte, representado por esferas de vidro industrializadas, contaram com uma etapa inicial de testes no intuito de desenvolver as metodologias de adensamento, de saturação e de drenagem. A contaminação somente se deu após a delineação do perfil dos ensaios. Com a finalidade de avaliar a mobilidade do contaminante na coluna de solo, após 24 horas foram realizadas as análises por extração e determinação gravimétrica de hidrocarbonetos totais de petróleo (TPH) e a ressonância magnética nuclear (RMN) das amostras de solo de cada segmento. Os resultados obtidos mostraram que o contaminante migrou facilmente através da coluna de solo arenoso. Os ensaios com o solo residual consistiram na contaminação de colunas de solo indeformado pelo mesmo óleo utilizado nos ensaios com o solo inerte, sob duas condições distintas: Sob a ação de refletores e em condições normais de temperatura. Foram realizadas análises químicas (TPH e RMN) e de atividade degradadora microbiana a cada 5cm, a fim de avaliar a influência dos microorganismos do solo no processo de degradação do contaminante ao longo dos 157 dias de monitoramento. Os resultados obtidos indicaram que o óleo é susceptível aos processos de biodegradação pela microbiota nativa, mostrando uma relação direta entre a atividade degradadora dos microrganismos do solo e a queda na concentração de hidrocarbonetos de petróleo. / [en] Petroleum hydrocarbons´ mobility and remediation processes to which they are submitted are of great importance to the management of contaminated areas. The investigation of tropical residual soils is of valuable contribution to the scientific community, not only in Brazil but also across the world, once there is little research work concerning the behavior of organic contaminants in these soils. The main goal of the present thesis was to study the mobility of a mineral oil in sandy and tropical residual silty soils. Since the latter constitutes a microbiologically active soil, both the biodegradation processes of the contaminant and the influence of temperature on its mobility through the porous media and on the degrading activity of the microbial population inhabiting the soil have been evaluated. The experiments regarding the sandy idle soil, represented by perfect industrialized spheres, counted on a initial stage of tests, in order to develop the methodologies most adequate to a situation where the capillary fringe does not represent a considerable portion of the column´s height. The contamination itself only took place after the outline of the whole experiment. With the purpose of analyzing the contaminant´s mobility after 24 hours, every sample of soil from each different section of the column has been chemically and microbiologically analyzed. The results have shown that the mineral oil migrated easily through the porous media. The experiments making use of the tropical residual soil consisted on the contamination of soil columns through their top by the same mineral oil applied to the first experiment. However the experiment took place under two distinct conditions: Under an increase of temperature (represented by the influence of reflectors) and under natural conditions of temperature. The bioremediation of soils contaminated by petroleum hydrocarbons is a multidisciplinary technology which involves sciences such as microbiology, engineering, geology and chemistry, and is based on the ability of microorganisms to utilize contaminants as an exclusive source of energy for the functioning of their metabolisms. Therefore, on the experiments in which the residual soil was the object of investigation, soil samples from the columns´ overture day have been subject to chemical (TPH and MNR) e microbiological (FDA) analysis in order to evaluate the influence of soil microorganisms on the biodegradation processes of the mineral oil throughout the 157 days of experiments. The results have shown that the tropical residual soil studied in the present work is susceptible to the biodegradation processes and is characterized by a direct relationship between the degradative activity and the loss of petroleum hydrocarbons.

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GoM) in the spring of 2010 introduced 4.4 million of barrels of oil to the ecosystem. Some biodegradation of the oil occurs when microorganisms, particularly bacteria, metabolize the oil as a carbon source. During this process, the microbes also require nutrients for energy. An introduction of oil at this magnitude has the ability to induce large blooms of microbes, which in turn can affect nutrient concentrations. Microbial petroleum degradation decreases nutrient concentrations, whereas the microbial assimilation and decay of organic matter increase nutrient concentrations. This study assessed whether any changes in nitrate, ammonium, and/or phosphate concentrations from historical levels could be attributed to the oil spill as a result of biodegradation, and how those changes can impact the GoM ecosystem. Nutrient samples were collected at discrete depths throughout the water column, in a cross-shelf transect inland from the spill site outside the DeSoto Canyon, in August 2010, February 2011, and May 2011 (four months to one year after the spill). In August 2010, a subsurface oil plume was found at depths of 1000 m to 1200 m. At the same depth of ~1000 m, a significant decrease in nitrate was observed, indicating the biodegradation of oil by heterotrophic bacteria of the aphotic zone, compared to earlier data during August 2000, when no known oils were present. Overall temporal increases in ammonium and dissolved organic nitrogen (DON) were observed both in near-surface waters and at an intermediate depth of ~400 m next to the walls of the DeSoto Canyon, suggesting an incremental die-off of both plankton and benthic organisms during accelerated recycling of nutrients. Continued decreases of phosphate were observed into February 2011, supporting ongoing biodegradation then as well. By May 2011, however, there were more increases in near-surface ammonium concentrations, compared to April 2000, with the implication that continued interseasonal recycled nitrogen accumulations may have been due to a decadal ecological regime shift, after a combination of top-down overfishing, petroleum perturbations, and/or increases of toxic harmful algal blooms (HABs).

La réhabilitation des sols pollués par les Hydrocarbures Aromatiques Polycycliques (HAP) est une problématique importante au niveau européen. Afin de développer une technique de bioremédiation, une collection de 30 souches de champignons saprotrophes est constitués à partir d'échantillons de sols historiquement pollués par les HAP provenant du Nord de la France. Ces souches sont caractérisées pour leur capacités de désorption et de dégradation du Benzo[a]pyrène (BaP) en milieu minéral. Quatre souches présentent des taux de dégradation du BaP supérieur à 30% après seulement 9 jours d'incubation en milieu minéral. Des mesures d'activités enzymatiques sur un panel de 14 souches permettent d'observer des concordances intéressantes entre les capacités de dégradation du BaP et des activités enzymatiques extracellulaires ou liées au cytochrome P450. Des essais au laboratoire de bioaugmentation/biostimulation en microcosmes de sols historiquement contaminés en HAP permettent une augmentation d'environ 25% de la dégradation des HAP totaux par rapport aux témoins après inoculation d'une souche de Talaromyceshelicus dans deux sols d'origines et de textures différentes. Le processus d'incorporation du BaP, un HAP à 5 cycles aromatiques, est étudié en microscopie chez une souche de Fusariumsolani. D'après nos résultats, cette molécule serait incorporée dans les cellules fongiques par un processus actif et dépendant du réseau d'actine du cytosquelette. Ce travail de thèse ouvre ainsi de nouvelles perspectives pour la compréhension des mécanismes de dégradation des HAP par les champignons saprotrophes telluriques et le développement de nouveaux protocoles de bioremédiation fongique des sols. / Recovery of soils polluted by Polycyclic Aromatic Hydrocarbons (PAH) is an important problematic at the European scale. In order to develop a bioremediation technique, a collection of 30 saprotrophic fungal strains is constituted using PAH historically contamined soil samples coming from the north of France. These strains are characterized for their capacity of Benzo[a]pyrene (BaP) desorption and degration in mineral medium. Four strains exhibit BaP degradation rates over 30% after 9 days of incubation in mineral medium. Measurements of enzymatic activities within a panel of 14 strains enable to observe interesting correlations between BaP degradation capacities and extracellular or cytochrome P450-linked enzymatic activities. Lab-scale bioaugmentation/biostimulation experiments in microcosms of PAH historically contamined soils enbale to observe an increase of approximately 25% of the total-PAH degradation compared to the blanks after the inoculation of a strain of Talaromyceshelicus in two soils differing by their origins and textures. The incorporation of BaP, a 5 aromatic rings PAH, is studied through microcopy in the strain Fusariumsolani. According to our results, this molecule would be incorporated in fungal cells through an active mechanism depending on the actin network of the cytoskeleton. This PhD thesis draws new perpectives for the understanding of PAH degradations mechanisms in telluric saprotrophic fungi and for the development of new fungal bioremediation protocols in soils.

Faecal contamination in water is detected using appropriate microbial models such as total coliforms, faecal coliforms and E. coli. Βeta-D-Galactosidase (β-GAL) and Beta-D-glucuronidase (β-GUD) are two marker enzymes that are used to test for the presence of total coliforms and E. coli in water samples, respectively. Various assay methods have been developed using chromogenic and fluorogenic substrates. In this study, the chromogenic substrates chlorophenol red β-D-galactopyranoside (CPRG) for β-GAL and p-nitrophenyl-β-D-galactopyranoside (PNPG) for β-GUD were used. Potential problems associated with this approach include interference from other organisms present in the environment (e.g. plants, algae and other bacteria), as well as the presence of certain chemicals, such as phenolic compounds in water. Phenolic compounds are present in the aquatic environment due to their extensive industrial applications. The USA Enviromental Protection Agency (EPA) lists 11 Priority Pollutant Phenols (PPP) due to their high level of toxicity. This study investigated the interfering effects of the eleven PPP found in water on the enzyme activities of both the β-GAL and β-GUD enzyme assays. The presence of these PPP in the β-GAL and β-GUD enzyme assays showed that over and underestimation of activity may occur due to inhibition or activation of these enzymes. Three types of inhibition to enzyme activities were identified from double reciprocal Lineweaver-Burk plots. The inhibition constants (Ki) were determined for all inhibitory phenolic compounds from appropriate secondary plots. Furthermore, this study presented a validated reverse phase high performance liquid chromatography (RP-HPLC) method, developed for the simultaneous detection, separation and determination of all eleven phenolic compounds found in the environment. This method demonstrated good linearity, reproducibility, accuracy and sensitivity. Environmental water samples were collected from rivers, streams, industrial sites and wastewater treatment plant effluent. These samples were extracted and concentrated using a solid phase extraction (SPE) procedure prior to analysis employing the newly developed HPLC method in this study. Seasonal variations on the presence of the PPP in the environment were observed at certain collection sites. The concentrations found were between 0.033 μg/ml for 2,4-dinitrophenol in a running stream to 0.890 mg/ml for pentachlorophenol from an tannery industrial site. These concentrations of phenolic compounds found in these environments were able to interfere with the β-GAL and β-GUD enzyme assays.

A variety of aquatic bacteria were isolated and tested for their ability to degrade humic substances and their aromatic residues/monomers which serve as precursors of the trihalomethanes (THMs) found in chlorinated drinking waters. The majority of them were Gram-negative, oxidative types dominated by pseudomonads. Most of the 146 isolates were found to utilize as their sole source of carbon several or more of ten aromatic compounds known to be products of degradation of humus and also to be precursors of THMs. The aromatics tested, with percent of the isolates utilizing the compound in parentheses, were: p-hydroxybenzoate (49), vanillic acid (48), 3,5-dihydroxybenzoic acid (16), syringic acid (19), vanillin (30), benzoic acid (27), ferulic acid (34), resorcinol (9), catechol (8) and protocatechuic acid (27).

Abstract In this work a manometric respirometric measuring system was applied to practical environmental cases related to wastewater management and biodegradation studies of oil-contaminated soils and materials used in landfill structures. Pollution of groundwater, surface water and soils is a worldwide problem. Therefore, tests simulating the biodegradation behaviour of organic compounds in water media and soils have become increasingly important. Respirometric methods provide direct measurement of the oxygen consumed by micro-organisms in biodegradation processes from an air or oxygen-enriched environment in a closed vessel. Biochemical oxygen demand (BOD) is a crucial environmental parameter used to measure the quality of water and treatment results in wastewater. Generally, BOD is measured with standardised methods, which are usually time-consuming as well as laborious. In this work the manometric respirometric test was compared with conventional BOD tests by determining the BOD of pulp and paper mills as well as domestic wastewater samples. The effect of different factors such as type, amount and pre-treatment of inoculum and the effect of dilution of a sample on the BOD values were also tested. A right dilution was noticed to be the most significant factor affecting the BOD values of the industrial wastewater samples. The mathematic estimation of the BOD7 values from the respirometric data was proved to work reliably after a 2–3 day incubation period. Characterisation of organic fractions of the pulp and paper mill wastewater was carried out with methods including filtration, long term BOD measurements and COD analyses. The most significant observation in characterisation analyses was that a remarkable part of the detected oxygen demand was consumed for the biotransformation of biodegradable fractions into new inert decomposition products, not only for mineralisation of the biodegradable COD fraction. Biodegradation behaviour of the peat samples with different decomposition rates was studied in order to evaluate the applicable peat types that can be used in landfill structures. Only minor (BOD/ThOD < 0.4%) biodegradation was observed with compaction peat samples, and the stable state, in which biodegradation stopped, was achieved during a two month period. The manometric respirometric method was also applied for the biodegradation studies in which the effect of the modification of soil properties on biodegradation rates of bio-oils was tested. Modified properties were the nutrient content and the pH of the soil. Fertiliser addition and pH adjustment increased both the BOD/ThOD% values of the model substances and the precision of the measurement. The manometric respirometric method was proved to be an advanced method for simulating biodegradation processes in soil and water media.

Acid mine drainage is a well known environmental pollutant, not only in South Africa, but throughout the world, and the use of microbial processes in the treatment of these wastes has been the subject of investigation over past decades. Lignocellulose packed-bed reactors have been used in passive treatment systems, and, although effective initially, they show early decline in performance while the packing material remains largely un-utilized. Little is known about this phenomenon which remains a severe constraint in the development of efficient passive mine water treatment systems. It has been proposed that the degradation pathways of the complex lignocellulose substrate may be limited in some way in these systems during the manifestation of this effect. This study has addressed the problem using a molecular microbial ecology methodology in an attempt to relate trophic functions of the microbial population to the physico-chemical data of the system. A field-scale lignocellulose packed-bed reactor located at Vryheid Coronation Colliery (Northern Kwa-Zulu Natal province, South Africa) was monitored for six years and the results showed the classic profile of performance decline related to a slowdown in sulphate reduction and alkalinity production. The reactor was decommissioned , comprehensive samples were collected along the depth profile and the microbial populations investigated by means of 16S rRNA gene methodology. The population was found to include cellulolytic Clostridia spp., CytophagaIFlavobacterlBacteroidetes, Sphingomonadaceae and as yet uncultured microorganisms related to microbiota identified in the rumen and termite gut. These are all known to be involved as primary fermenters of cellulose. Oesulphosporosinus was present as sulphate reducer. A comparison of substrata sampling and population distribution suggested that spatial and temporal gradients within the system may become established over the course of its operation. Based on these findings, a laboratory-scale reactor was constructed to simulate the performance of the packed-bed reactor under controlled experimental conditions. The laboratory-scale reactor was operated for 273 days and showed comparable performance to that in the field in both biomolecular and physicochemical data. Clearly defined trophic niches were observed. These results suggested that a sequence of events does occur in lignocellulose degradation over time. Based on the spatial and temporal column studies, a descriptive model was proposed to account for these events. It was found that fermentative organisms predominate in the inlet zone of the system using easily extractable compounds from the wood, thus providing feedstock for sulphate reduction occurring in the succeeding compartments. Production of sulphide and alkalinity appears to be involved in the enhancement of lignin degradation and this, in turn, appears to enhance access to the cellulose fraction. However, once the readily extractables are exhausted, the decline in sulphide and alkalinity production leads inexorably to a decline in the overall performance of the system as a sulphate reducing unit operation. These observations led to the proposal that with the addition of a limited amount of a readily available carbon source, such as molasses, in the initial zone of the the reactor, the ongoing generation of sulphide would be sustained and this in turn would sustain the microbial attack on the lignocellulose complex. This proposal was tested in scale-up studies and positive results indicate that the descriptive model may, to some extent, provide an account of events occurring in these systems. The work on sustaining lignocellulose degradation through the maintenance of sulphate reduction in the initial stages of the reactor flow path has led to the development of the Degrading Packed-bed Reactor concept and that, has subsequently been successfully evaluated in the field.